mtd: move zero length verification to MTD API functions
In many places in drivers we verify for the zero length, but this is very
inconsistent across drivers. This is obviously the right thing to do, though.
This patch moves the check to the MTD API functions instead and removes a lot
of duplication.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c
index dc66df6..2d96690 100644
--- a/drivers/mtd/chips/cfi_cmdset_0001.c
+++ b/drivers/mtd/chips/cfi_cmdset_0001.c
@@ -1566,9 +1566,6 @@
int chipnum;
unsigned long ofs;
- if (!len)
- return 0;
-
chipnum = to >> cfi->chipshift;
ofs = to - (chipnum << cfi->chipshift);
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index a89d899..c1d4624 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -1246,9 +1246,6 @@
unsigned long ofs, chipstart;
DECLARE_WAITQUEUE(wait, current);
- if (!len)
- return 0;
-
chipnum = to >> cfi->chipshift;
ofs = to - (chipnum << cfi->chipshift);
chipstart = cfi->chips[chipnum].start;
@@ -1487,9 +1484,6 @@
int chipnum;
unsigned long ofs;
- if (!len)
- return 0;
-
chipnum = to >> cfi->chipshift;
ofs = to - (chipnum << cfi->chipshift);
@@ -1697,9 +1691,6 @@
int ret = 0;
int chipnum;
- if (!len)
- return 0;
-
chipnum = to >> cfi->chipshift;
ofs = to - (chipnum << cfi->chipshift);
chipstart = cfi->chips[chipnum].start;
diff --git a/drivers/mtd/chips/cfi_cmdset_0020.c b/drivers/mtd/chips/cfi_cmdset_0020.c
index d690b7d..096993f 100644
--- a/drivers/mtd/chips/cfi_cmdset_0020.c
+++ b/drivers/mtd/chips/cfi_cmdset_0020.c
@@ -615,9 +615,6 @@
int chipnum;
unsigned long ofs;
- if (!len)
- return 0;
-
chipnum = to >> cfi->chipshift;
ofs = to - (chipnum << cfi->chipshift);
diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index ba2d74b..a4a80b7 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -178,9 +178,6 @@
struct block2mtd_dev *dev = mtd->priv;
int err;
- if (!len)
- return 0;
-
mutex_lock(&dev->write_mutex);
err = _block2mtd_write(dev, buf, to, len, retlen);
mutex_unlock(&dev->write_mutex);
diff --git a/drivers/mtd/devices/lart.c b/drivers/mtd/devices/lart.c
index 6fb8dba..82bd00a 100644
--- a/drivers/mtd/devices/lart.c
+++ b/drivers/mtd/devices/lart.c
@@ -437,9 +437,6 @@
printk (KERN_DEBUG "%s(from = 0x%.8x, len = %d)\n", __func__, (__u32)from, len);
#endif
- /* sanity checks */
- if (!len) return (0);
-
/* we always read len bytes */
*retlen = len;
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 45cc4a1..1924d24 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -346,10 +346,6 @@
pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
__func__, (u32)from, len);
- /* sanity checks */
- if (!len)
- return 0;
-
spi_message_init(&m);
memset(t, 0, (sizeof t));
@@ -408,10 +404,6 @@
pr_debug("%s: %s to 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
__func__, (u32)to, len);
- /* sanity checks */
- if (!len)
- return(0);
-
spi_message_init(&m);
memset(t, 0, (sizeof t));
@@ -495,10 +487,6 @@
pr_debug("%s: %s to 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
__func__, (u32)to, len);
- /* sanity checks */
- if (!len)
- return 0;
-
spi_message_init(&m);
memset(t, 0, (sizeof t));
diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c
index c76b446..928fb0e 100644
--- a/drivers/mtd/devices/mtd_dataflash.c
+++ b/drivers/mtd/devices/mtd_dataflash.c
@@ -249,10 +249,6 @@
pr_debug("%s: read 0x%x..0x%x\n", dev_name(&priv->spi->dev),
(unsigned)from, (unsigned)(from + len));
- /* Sanity checks */
- if (!len)
- return 0;
-
/* Calculate flash page/byte address */
addr = (((unsigned)from / priv->page_size) << priv->page_offset)
+ ((unsigned)from % priv->page_size);
@@ -321,10 +317,6 @@
pr_debug("%s: write 0x%x..0x%x\n",
dev_name(&spi->dev), (unsigned)to, (unsigned)(to + len));
- /* Sanity checks */
- if (!len)
- return 0;
-
spi_message_init(&msg);
x[0].tx_buf = command = priv->command;
@@ -479,8 +471,6 @@
if ((off + len) > 64)
len = 64 - off;
- if (len == 0)
- return len;
spi_message_init(&m);
diff --git a/drivers/mtd/devices/spear_smi.c b/drivers/mtd/devices/spear_smi.c
index 2cdbcc6..f45dd37 100644
--- a/drivers/mtd/devices/spear_smi.c
+++ b/drivers/mtd/devices/spear_smi.c
@@ -563,9 +563,6 @@
u32 ctrlreg1, val;
int ret;
- if (!len)
- return 0;
-
if (!flash || !dev)
return -ENODEV;
@@ -662,9 +659,6 @@
if (!flash || !dev)
return -ENODEV;
- if (!len)
- return 0;
-
if (flash->bank > dev->num_flashes - 1) {
dev_err(&dev->pdev->dev, "Invalid Bank Num");
return -EINVAL;
diff --git a/drivers/mtd/devices/sst25l.c b/drivers/mtd/devices/sst25l.c
index 5c2613c..51b2df3 100644
--- a/drivers/mtd/devices/sst25l.c
+++ b/drivers/mtd/devices/sst25l.c
@@ -220,10 +220,6 @@
unsigned char command[4];
int ret;
- /* Sanity checking */
- if (len == 0)
- return 0;
-
spi_message_init(&message);
memset(&transfer, 0, sizeof(transfer));
@@ -265,10 +261,6 @@
int i, j, ret, bytes, copied = 0;
unsigned char command[5];
- /* Sanity checks */
- if (!len)
- return 0;
-
if ((uint32_t)to % mtd->writesize)
return -EINVAL;
diff --git a/drivers/mtd/lpddr/lpddr_cmds.c b/drivers/mtd/lpddr/lpddr_cmds.c
index a92906b..d3cfe26b 100644
--- a/drivers/mtd/lpddr/lpddr_cmds.c
+++ b/drivers/mtd/lpddr/lpddr_cmds.c
@@ -639,7 +639,6 @@
int chipnum;
unsigned long ofs, vec_seek, i;
int wbufsize = 1 << lpddr->qinfo->BufSizeShift;
-
size_t len = 0;
for (i = 0; i < count; i++)
diff --git a/drivers/mtd/maps/vmu-flash.c b/drivers/mtd/maps/vmu-flash.c
index 48a803e..2e2b094 100644
--- a/drivers/mtd/maps/vmu-flash.c
+++ b/drivers/mtd/maps/vmu-flash.c
@@ -360,9 +360,6 @@
int index = 0, retval, partition, leftover, numblocks;
unsigned char cx;
- if (len < 1)
- return -EIO;
-
mpart = mtd->priv;
mdev = mpart->mdev;
partition = mpart->partition;
@@ -434,11 +431,6 @@
partition = mpart->partition;
card = maple_get_drvdata(mdev);
- /* simple sanity checks */
- if (len < 1) {
- error = -EIO;
- goto failed;
- }
numblocks = card->parts[partition].numblocks;
if (to + len > numblocks * card->blocklen)
len = numblocks * card->blocklen - to;
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index b20346e..6acc4fb 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -695,6 +695,11 @@
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
+ if (!instr->len) {
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+ return 0;
+ }
return mtd->_erase(mtd, instr);
}
EXPORT_SYMBOL_GPL(mtd_erase);
@@ -713,6 +718,8 @@
return -EOPNOTSUPP;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_point(mtd, from, len, retlen, virt, phys);
}
EXPORT_SYMBOL_GPL(mtd_point);
@@ -724,6 +731,8 @@
return -EOPNOTSUPP;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_unpoint(mtd, from, len);
}
EXPORT_SYMBOL_GPL(mtd_unpoint);
@@ -750,6 +759,8 @@
*retlen = 0;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_read(mtd, from, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_read);
@@ -762,6 +773,8 @@
return -EINVAL;
if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
return -EROFS;
+ if (!len)
+ return 0;
return mtd->_write(mtd, to, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_write);
@@ -783,6 +796,8 @@
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
+ if (!len)
+ return 0;
return mtd->_panic_write(mtd, to, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_panic_write);
@@ -794,6 +809,8 @@
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_lock(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_lock);
@@ -804,6 +821,8 @@
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_unlock(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_unlock);
@@ -814,6 +833,8 @@
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
+ if (!len)
+ return 0;
return mtd->_is_locked(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_is_locked);
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index dd182c8..5822e3a 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1614,9 +1614,6 @@
struct mtd_oob_ops ops;
int ret;
- if (!len)
- return 0;
-
nand_get_device(chip, mtd, FL_READING);
ops.len = len;
ops.datbuf = buf;
@@ -2313,10 +2310,6 @@
struct mtd_oob_ops ops;
int ret;
- /* Do not allow reads past end of device */
- if (!len)
- return 0;
-
/* Wait for the device to get ready */
panic_nand_wait(mtd, chip, 400);
@@ -2351,9 +2344,6 @@
struct mtd_oob_ops ops;
int ret;
- if (!len)
- return 0;
-
nand_get_device(chip, mtd, FL_WRITING);
ops.len = len;
ops.datbuf = (uint8_t *)buf;